The 89th district included all or parts of Marshall, McLean, Stark, Tazewell, and Woodford counties in north-central Illinois.

[12] Koehler defeated Inland Steel executive George Ranneywik in the Republican primary,[15][16] but was unable to oust incumbent Alan Dixon in the general election.

[11] She was succeeded in the Illinois House of Representatives by John "Jay" Ackerman, who she had defeated in the 1982 Republican primary for the seat.

[17] In 1992, a graduate of Loyola University Chicago School of Law, Koehler was admitted to the Illinois State Bar.

[20] In 1994, Koehler ran for U.S. Congress in Illinois's 18th congressional district to replace the retiring Republican Robert H. Michel.